Congenital Absence oJ the Flexor Pollicis Longus--A Case Report--Takayuki Miura
CONGENITAL ABSENCE OF THE FLEXOR POLLICIS LONGUS A CASE REPORT TAKAYUKI MIURA, Nagoya, Japan SUMMARY Congenital absence of the flexor pollicis Iongus, associated with hypoplasia of the thumb, is an unusual anomaly. A case of congenital absence of the flexor polficis longus without hypoplasia or aplasia of the thumb and thenar muscles, which is described, is very rare. Surgical treatment for the transfer of the ring finger flexor superficialis tendon to provide the thumb interphalangeal joint with flexion resulted in a significant improvement in pinch. INTRODUCTION The absence of the flexor pollicis longus, associated with aplasia of the thenar muscles, was first described by Froment in 1895, and several articles have since then been published (Salama, 1975; Strauch, 1976, Tsuchida, 1975, Tupper, 1969). On the other hand, there seems to be only one case report (Tsuchida, 1975) on a case of congenital absence of the flexor pollicis longus without any abnormalities of the thenar muscles and osseous structures of the thumb. CASE REPORT A one-year-old girl, came to our clinic in April 1974, with the complaint that the interphalangeal joint of her right thumb could not flex voluntarily. Her family history showed no anomalies of the hand. Examination disclosed that the skin creases were absent from the interphalangeal joint of the thumb, and active flexion at this joint was impossible, though passive flexion through 40 degrees was possible. Flexion of the metacarpophalangeal joint, adduction and abduction of the thumb were normal. There was no hypotrophy of the thenar eminence, which was comparable to that of the left hand. Sensation seemed to be normal. X-ray examination revealed no skeletal deficiencies (Fig. 1). Operative treatment to give thumb interphalangeal joint flexion was performed in January, 1976. The ring finger flexor superficialis tendon was detached at its insertion, and re-routed to that of the absent flexor pollicis longus tendon, and inserted into the base of the distal phalanx, using Bunnell's pull-out technique. The following abnormalities were revealed at operation. 1. Three tendinous bundles, which seemed to be flexor pollicis longus, were raised from the fascia of the thenar muscles, and ran to the volar side of the distal phalanx (Fig. 2). 2. No evidence of flexor pollicis longus muscle was found in the forearm, though all the other flexor muscles were normal. The hand was immobilized for three weeks by a plaster cast. with the wrist in fifteen degree volar flexion. Takayuki Miura, M.D., Branch Hospital, Nagoya University School of Medicine, 2-12-1, Higashisakura, Higashiku, Nagoya, Japan. 272
The Hand--Vol. 9
No. 3
1977
Congenital Absence of the Flexor Pollicis Longus--A Case Report--Takayuki Miura
Fig. 1. X-ray of the hand showing normal bone structure.
Fig. 2. Three tendinous bundles are raised from the fascia of the thenar muscles, and run to the volar aspect of the distal phalanx. One year after surgery, the t h u m b interphalangeal joint is capable of only twenty degrees of active flexion, but she is able to perform numerous precision activities which she was unable to do previously. The Hand--Vol. 9
No. 3
1977
273
Congenital Absence of the Flexor Pollicis Longus--A Case Report---Takayuki Miura
REFERENCES
CRAWFORD, H. H., HORTON, C. E. and ADAMSON, J. E. (1966) Congenital Aplasia or Hypoplasia of the Thumb and Finger Extensor Tendons. Journal of Bone and Joint Surgery, 48A" 82-91. FROMENT, (1895) Anomalies musculaires multiples de la main. Absence du fl6chisseur propre du pouce. Absence des muscles de l'6minence thenar. Lombricaux Suppl6mentaires. Bulletins de la Soci6t6 Anatomique de Paris, IX: 395-401. SALAMA, R. and WEISSMAN, S. L. (1975) Congenital Bilateral Anomalous Band Between Flexor and Extensor Pollicis Longus Tendons. The Hand, 7: 25-26. STRAUCH, B. and SPINNER, M. (1976) Congenital Anomaly of the Thumb: Absent Intrinsics and Flexor Pollicis Longus. Journal of Bone and Joint Surgery, 58A: 115-118. TSUCHIDA, Y., KASSAI, S. and KOJIMA, T. (1975) Congenital Absence of Flexor Pollicis Longus and Brevis. A Case Report. The Hand, 8: 294-297. TUPPER, J. W, (1969) Pollex Abductus Due to Congenital Malposition of the Flexor Pollicis Longus. Journal of Bone and Joint Surgery, 51A: 1285-1289.
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1977
CONGENITAL ABSENCE OF THE FLEXOR POLLICIS LONGUS A CASE REPORT TAKAYUKI MIURA, Nagoya, Japan SUMMARY Congenital absence of the flexor pollicis Iongus, associated with hypoplasia of the thumb, is an unusual anomaly. A case of congenital absence of the flexor polficis longus without hypoplasia or aplasia of the thumb and thenar muscles, which is described, is very rare. Surgical treatment for the transfer of the ring finger flexor superficialis tendon to provide the thumb interphalangeal joint with flexion resulted in a significant improvement in pinch. INTRODUCTION The absence of the flexor pollicis longus, associated with aplasia of the thenar muscles, was first described by Froment in 1895, and several articles have since then been published (Salama, 1975; Strauch, 1976, Tsuchida, 1975, Tupper, 1969). On the other hand, there seems to be only one case report (Tsuchida, 1975) on a case of congenital absence of the flexor pollicis longus without any abnormalities of the thenar muscles and osseous structures of the thumb. CASE REPORT A one-year-old girl, came to our clinic in April 1974, with the complaint that the interphalangeal joint of her right thumb could not flex voluntarily. Her family history showed no anomalies of the hand. Examination disclosed that the skin creases were absent from the interphalangeal joint of the thumb, and active flexion at this joint was impossible, though passive flexion through 40 degrees was possible. Flexion of the metacarpophalangeal joint, adduction and abduction of the thumb were normal. There was no hypotrophy of the thenar eminence, which was comparable to that of the left hand. Sensation seemed to be normal. X-ray examination revealed no skeletal deficiencies (Fig. 1). Operative treatment to give thumb interphalangeal joint flexion was performed in January, 1976. The ring finger flexor superficialis tendon was detached at its insertion, and re-routed to that of the absent flexor pollicis longus tendon, and inserted into the base of the distal phalanx, using Bunnell's pull-out technique. The following abnormalities were revealed at operation. 1. Three tendinous bundles, which seemed to be flexor pollicis longus, were raised from the fascia of the thenar muscles, and ran to the volar side of the distal phalanx (Fig. 2). 2. No evidence of flexor pollicis longus muscle was found in the forearm, though all the other flexor muscles were normal. The hand was immobilized for three weeks by a plaster cast. with the wrist in fifteen degree volar flexion. Takayuki Miura, M.D., Branch Hospital, Nagoya University School of Medicine, 2-12-1, Higashisakura, Higashiku, Nagoya, Japan. 272
The Hand--Vol. 9
No. 3
1977
Congenital Absence of the Flexor Pollicis Longus--A Case Report--Takayuki Miura
Fig. 1. X-ray of the hand showing normal bone structure.
Fig. 2. Three tendinous bundles are raised from the fascia of the thenar muscles, and run to the volar aspect of the distal phalanx. One year after surgery, the t h u m b interphalangeal joint is capable of only twenty degrees of active flexion, but she is able to perform numerous precision activities which she was unable to do previously. The Hand--Vol. 9
No. 3
1977
273
Congenital Absence of the Flexor Pollicis Longus--A Case Report---Takayuki Miura
REFERENCES
CRAWFORD, H. H., HORTON, C. E. and ADAMSON, J. E. (1966) Congenital Aplasia or Hypoplasia of the Thumb and Finger Extensor Tendons. Journal of Bone and Joint Surgery, 48A" 82-91. FROMENT, (1895) Anomalies musculaires multiples de la main. Absence du fl6chisseur propre du pouce. Absence des muscles de l'6minence thenar. Lombricaux Suppl6mentaires. Bulletins de la Soci6t6 Anatomique de Paris, IX: 395-401. SALAMA, R. and WEISSMAN, S. L. (1975) Congenital Bilateral Anomalous Band Between Flexor and Extensor Pollicis Longus Tendons. The Hand, 7: 25-26. STRAUCH, B. and SPINNER, M. (1976) Congenital Anomaly of the Thumb: Absent Intrinsics and Flexor Pollicis Longus. Journal of Bone and Joint Surgery, 58A: 115-118. TSUCHIDA, Y., KASSAI, S. and KOJIMA, T. (1975) Congenital Absence of Flexor Pollicis Longus and Brevis. A Case Report. The Hand, 8: 294-297. TUPPER, J. W, (1969) Pollex Abductus Due to Congenital Malposition of the Flexor Pollicis Longus. Journal of Bone and Joint Surgery, 51A: 1285-1289.
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